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arXiv · 2501.02060

The MAJORANA DEMONSTRATOR experiment's construction, commissioning, and performance

Abstract

Background: The MAJORANA DEMONSTRATOR , a modular array of isotopically enriched high-purity germanium (HPGe) detectors, was constructed to demonstrate backgrounds low enough to justify building a tonne-scale experiment to search for the neutrinoless double-beta decay ($\beta\beta(0\nu)$) of $^{76}\mathrm{Ge}$. Purpose: This paper presents a description of the instrument, its commissioning, and operations. It covers the electroforming, underground infrastructure, enrichment, detector fabrication, low-background and construction techniques, electronics, data acquisition, databases, and data processing of the MAJORANA DEMONSTRATOR. Method: The MAJORANA DEMONSTRATOR operated inside an ultra-low radioactivity passive shield at the 4850-foot~level of the Sanford Underground Research Facility (SURF) from 2015-2021. Results and Conclusions: The MAJORANA DEMONSTRATOR achieved the best energy resolution and second-best background level of any $\beta\beta(0\nu)$ search. This enabled it to achieve an ultimate half-life limit on $\beta\beta(0\nu)$ in $^{76}\mathrm{Ge}$ of $8.3\times 10^{25}$~yr (90\% C.L.) and perform a rich set of searches for other physics beyond the Standard Model.

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N. Abgrall, E. Aguayo, I. J. Arnquist, F. T. Avignone III, A. S. Barabash, C. J. Barton, P. J. Barton, F. E. Bertrand, E. Blalock, B. Bos, M. Boswell, A. W. Bradley, V. Brudanin, T. H. Burritt, M. Busch, M. Buuck, D. Byram, A. S. Caldwell, T. S. Caldwell, Y. -D. Chan, C. D. Christofferson, P. -H. Chu, M. L. Clark, D. C. Combs, C. Cuesta, J. A. Detwiler, Yu. Efremenko, H. Ejiri, S. R. Elliott, J. E. Fast, P. Finnerty, F. M. Fraenkle, N. Fuad, E. Fuller, T. Gilliss, G. K. Giovanetti, J. Goett, M. P. Green, J. Gruszko, I. S. Guinn, V. E. Guiseppe, G. C. Harper, C. R. Haufe, R. Henning, D. Hervas Aguilar, E. W. Hoppe, A. Hostiuc, M. A. Howe, B. R. Jasinski, K. J. Keeter, M. F. Kidd, I. Kim, R. T. Kouzes, B. D. LaFerriere, T. E. Lannen V, A. Li, J. C. Loach, A. M. Lopez, J. M. Lopez-Castano, J. MacMullin, S. MacMullin, E. L. Martin, R. D. Martin, R. Massarczyk, S. J. Meijer, J. H. Merriman, S. Mertens, H. S. Miley, J. Myslik, T. K. Oli, J. L. Orrell, C. O'Shaughnessy, G. Othman, N. R. Overman, D. Peterson, W. Pettus, A. W. P. Poon, D. C. Radford, J. Rager, A. L. Reine, K. Rielage, R. G. H. Robertson, L. Rodriguez, N. W. Ruof, H. Salazar, D. C. Schaper, S. J. Schleich, B. Shanks, M. Shirchenko, K. J. Snavely, N. Snyder, A. Soin, D. Steele, A. M. Suriano, G. Swift, D. Tedeschi J. E. Trimble, M. Turqueti, T. D. Van Wechel, R. L. Varner, S. Vasilyev. 2025-01-03. The MAJORANA DEMONSTRATOR experiment's construction, commissioning, and performance. https://arxiv.org/abs/2501.02060

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